Download or read book Potential Flow Based Aerodynamic and Aeroelastic Analysis of Flapping Wings written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The motivation for this research is the importance that the modeling of aerodynamics and aeroelasticity of flapping wings has had in the last decade. The development of flapping wings Micro Air Vehicles (MAV) has captured a huge interest in the recent past, due to the several disciplines involved in the subject. In this dissertation the attention is focused on the flow and its interactions with the structure. Even though experiments have had a fundamental role in the explanation of the aerodynamics around a flapping wing, it is widely accepted that a key aspect in the development of future flapping wings MAVs is the modeling. The aim of the project is to investigate different techniques for the development of a numerical framework used in the prediction of the unsteady aerodynamic forces on flapping wings. The understanding of the phenomena occurring on flapping wings is attempted first with very basic models. The research is carried out based on potential flow assumptions: the flow in initially treated as irrotational and inviscid. Although the assumptions are very strong, it is shown that the mechanisms of lift and thrust production can be described, together with the convection of the wake behind the wing. The limitation of potential flow models is the incapacity to describe flows that are separated over a large portion of the wing. The modeling of this issue is particularly important for flapping wings, where the separation is exploited in order tin increase the forces produced. The development of a Vortex Particle Method (VPM) is attempted, with wake elements released at each time step from all the panels of the airfoil. The advantage of Vortex Particle Methods over panel methods is that they represent more realistically the flow around the wing. The drawback is the greater complexity and longer running times. Aeroelasticity is discussed as well, as it is believed that the wing flexibility can enhance the performance of flapping wings. The thesis investigates t.
Download or read book Potential Flow based Aerodynamics and Aeroelastic Analysis Pf Flapping Wings written by E. Liani and published by . This book was released on 2008 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Introduction to Flapping Wing Aerodynamics written by Wei Shyy and published by Cambridge University Press. This book was released on 2013-08-19 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an ideal book for graduate students and researchers interested in the aerodynamics, structural dynamics and flight dynamics of small birds, bats and insects, as well as of micro air vehicles (MAVs), which present some of the richest problems intersecting science and engineering. The agility and spectacular flight performance of natural flyers, thanks to their flexible, deformable wing structures, as well as to outstanding wing, tail and body coordination, is particularly significant. To design and build MAVs with performance comparable to natural flyers, it is essential that natural flyers' combined flexible structural dynamics and aerodynamics are adequately understood. The primary focus of this book is to address the recent developments in flapping wing aerodynamics. This book extends the work presented in Aerodynamics of Low Reynolds Number Flyers (Shyy et al. 2008).
Download or read book An Introduction to Flapping Wing Aerodynamics written by Wei Shyy and published by Cambridge University Press. This book was released on 2013-08-19 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: For anyone interested in the aerodynamics, structural dynamics and flight dynamics of small birds, bats, insects and air vehicles (MAVs).
Download or read book Unsteady Transonic Aerodynamic and Aeroelastic Calculations about Airfoils and Wings written by and published by . This book was released on 1984 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transonic Unsteady Aerodynamic and Aeroelastic Calculations about Airfoils and Wings written by and published by . This book was released on 1987 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aerodynamic Analysis of Natural Flapping Flight Using a Lift Model Based on Spanwise Flow written by Lionel D. Alford and published by . This book was released on 2010 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study successfully described the mechanics of flapping hovering flight within the framework of conventional aerodynamics. Additionally, the theory proposed and supported by this research provides an entirely new way of looking at animal flapping flight. The mechanisms of biological flight are not well understood, and researchers have not been able to describe them using conventional aerodynamic forces. This study proposed that natural flapping flight can be broken down into a simplest model, that this model can then be used to develop a mathematical representation of flapping hovering flight, and finally, that the model can be successfully refined and compared to biological flapping data. This paper proposed a unique theory that the lift of a flapping animal is primarily the result of velocity across the cambered span of the wing. A force analysis was developed using centripetal acceleration to define an acceleration profile that would lead to a spanwise velocity profile. The force produced by the spanwise velocity profile was determined using a computational fluid dynamics analysis of flow on the simplified wing model. The overall forces on the model were found to produce more than twice the lift required for hovering flight. In addition, spanwise lift was shown to generate induced drag on the wing. Induced drag increased both the model wing's lift and drag. The model allowed the development of a mathematical representation that could be refined to account for insect hovering characteristics and that could predict expected physical attributes of the fluid flow. This computational representation resulted in a profile of lift and drag production that corresponds to known force profiles for insect flight. The model of flapping flight was shown to produce results similar to biological observation and experiment, and these results can potentially be applied to the study of other flapping animals. This work provides a foundation on which to base further exploration and hypotheses regarding flapping flight.
Download or read book Aerial Robots written by Omar D Lopez Mejia and published by BoD – Books on Demand. This book was released on 2017-09-06 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Few years ago, the topic of aerial robots was exclusively related to the robotics community, so a great number of books about the dynamics and control of aerial robots and UAVs have been written. As the control technology for UAVs advances, the great interaction that exists between other systems and elements that are as important as control such as aerodynamics, energy efficiency, acoustics, structural integrity, and applications, among others has become evident. Aerial Robots - Aerodynamics, Control, and Applications is an attempt to bring some of these topics related to UAVs together in just one book and to look at a selection of the most relevant problems of UAVs in a broader engineering perspective.
Download or read book Unsteady Aerodynamics and Propulsive Characteristics of Flapping Wings with Applications to Avian Fight sic written by Michael Shawn Vest and published by . This book was released on 1996 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Propulsive forces can be generated with flapping or heaving wings traveling through a fluid, as demonstrated in animal flight. The flow field of a bird in flight is one of the most complex aerodynamic problems that can be examined. Many other bird flight theories are based on quasi-steady fluid dynamic assumptions even though the flow field is inherently unsteady. To help examine the time dependency of bird flight, an unsteady three dimensional potential flow panel code was developed. Another problem in studying the aerodynamics of avian flight is the limited amount of quantitative experimental data on flapping wings. To gain further understanding of avian flight and to develop an experimental database for comparison of the fluid dynamic model, a mechanical bird was constructed and placed in a wind tunnel. The mechanical bird, modeled after a pigeon, is capable of flapping at various angles to the freestream flow. For the current study, however, the flapping motion was limited to a plane normal to the oncoming flow. Results of the numerical model were compared to the measured forces on the mechanical bird as well as to the limited data available on real birds. In one case, the model was applied to a flapping wing in a wind tunnel at high advance ratios $(J=4.31)$ where the computed average lift and thrust were within the error bounds of the experimental data. The model was also applied to high frequency flapping flight $(J=0.76)$ of a pigeon flying in a wind tunnel, where the predicted lift matched the weight of the bird. Time histories of the mechanical pigeon agreed well with the numerical predictions for high $(J=5.38)$ and low $(J=0.84)$ advance ratios. The model was also extended to examine the effect of wing twist on flight efficiencies. Flight characteristics of the mechanical bird and a real pigeon were also compared.
Download or read book Relationship Between Flutter Parameters and Generalized Aerodynamic Forces for Wings of Low Aspect Ratio written by Bernard Mazelsky and published by . This book was released on 1962 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: A set of closed-form approximations is derived which relates the flutter conditions of a wing to its generalized aerodynamic forces. A simplified two-mode analysis is used to obtain a firstorder approximation. More general analyses are performed by treating additional effects as perturbations. The derivations are applicable to a wide class of low-aspect-ratio wings and apply to subsonic, transonic, supersonic, and hypersonic flow.
Download or read book Introduction to Aeroelasticity written by Harijono Djojodihardjo and published by Springer Nature. This book was released on 2023-09-03 with total page 1080 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook is intended as a core text for courses on aeroelasticity or aero-elasto-mechanics for senior undergraduate/graduate programs in aerospace and mechanical engineering. The book focuses on the basic understanding of the concepts required in learning about aeroelasticity, from observation, reasoning, and understanding fundamental physical principles. Fundamental and simple mathematics will be introduced to describe the features of aeroelastic problems, and to devise simple concurrent physical and mathematical modeling. It will be accompanied by the introduction and understandings of the mechanisms that create the interactions that generate the aeroelastic phenomena considered. The students will also be led to the relation between observed phenomena, assumptions that may have to be adopted to arrive at physical and mathematical modelling, interpreting and verifying the results, and the accompanied limitations, uncertainties and inaccuracies. The students will also be introduced to combine engineering problem solving attitude and determination with simple mechanics problem-solving skills that coexist harmoniously with a useful mechanical intuition.
Download or read book Aeroservoelasticity written by Ashish Tewari and published by Springer. This book was released on 2015-03-24 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph presents the state of the art in aeroservoelastic (ASE) modeling and analysis and develops a systematic theoretical and computational framework for use by researchers and practicing engineers. It is the first book to focus on the mathematical modeling of structural dynamics, unsteady aerodynamics, and control systems to evolve a generic procedure to be applied for ASE synthesis. Existing robust, nonlinear, and adaptive control methodology is applied and extended to some interesting ASE problems, such as transonic flutter and buffet, post-stall buffet and maneuvers, and flapping flexible wing. The author derives a general aeroservoelastic plant via the finite-element structural dynamic model, unsteady aerodynamic models for various regimes in the frequency domain, and the associated state-space model by rational function approximations. For more advanced models, the full-potential, Euler, and Navier-Stokes methods for treating transonic and separated flows are also briefly addressed. Essential ASE controller design and analysis techniques are introduced to the reader, and an introduction to robust control-law design methods of LQG/LTR and H2/H∞ synthesis is followed by a brief coverage of nonlinear control techniques of describing functions and Lyapunov functions. Practical and realistic aeroservoelastic application examples derived from actual experiments are included throughout. Aeroservoelasiticity fills an important gap in the aerospace engineering literature and will be a valuable guide for graduate students and advanced researchers in aerospace engineering, as well as professional engineers, technicians, and test pilots in the aircraft industry and laboratories.
Download or read book Wing Flutter Boundary Prediction Using an Unsteady Euler Aerodynamic Method written by Elizabeth M. Lee-Rausch and published by . This book was released on 1993 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Introduction to Nonlinear Aeroelasticity written by Grigorios Dimitriadis and published by John Wiley & Sons. This book was released on 2017-03-10 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Nonlinear Aeroelasticity Introduces the latest developments and technologies in the area of nonlinear aeroelasticity Nonlinear aeroelasticity has become an increasingly popular research area in recent years. There have been many driving forces behind this development, increasingly flexible structures, nonlinear control laws, materials with nonlinear characteristics and so on. Introduction to Nonlinear Aeroelasticity covers the theoretical basics in nonlinear aeroelasticity and applies the theory to practical problems. As nonlinear aeroelasticity is a combined topic, necessitating expertise from different areas, the book introduces methodologies from a variety of disciplines such as nonlinear dynamics, bifurcation analysis, unsteady aerodynamics, non-smooth systems and others. The emphasis throughout is on the practical application of the theories and methods, so as to enable the reader to apply their newly acquired knowledge Key features: Covers the major topics in nonlinear aeroelasticity, from the galloping of cables to supersonic panel flutter Discusses nonlinear dynamics, bifurcation analysis, numerical continuation, unsteady aerodynamics and non-smooth systems Considers the practical application of the theories and methods Covers nonlinear dynamics, bifurcation analysis and numerical methods Accompanied by a website hosting Matlab code Introduction to Nonlinear Aeroelasticity is a comprehensive reference for researchers and workers in industry and is also a useful introduction to the subject for graduate and undergraduate students across engineering disciplines.
Download or read book A Method for Calculating the Aerodynamic Forces Due to Arbitrary Time Dependent Downwash for a Class of Thin Flexible Wings at Supersonic Speeds written by Robert W. Warner and published by . This book was released on 1960 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2008 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
